Polymer crosslinked silica aerogels have been considered for various space-related applications due to their light weight (99.9% air) and yet high mechanical strength. Aerogels were invented in the 1930s and consist of a pearl-necklace-like network of skeletal nanoparticles, leaving more than 99% of their bulk volume empty. Chemically, the skeletal nanoparticles of most typical aerogels are made of silica. So far, the two major uses of aerogels have been as collectors of hypervelocity particles in space (Burchell 2009) upon NASA's Stardust Program and as thermal insulation of the electronic boxes on the Mars Rovers (Paul 2003). However, little work has been done on the biological applications of this class of materials.
Currently, materials of choice for nerve damage repair have been a variety of synthetic, polymeric, and biological [1-6] materials as well as those from the general category of hydrogels. Among the currently used implant materials, problems such as sagging, nerve pinching, and swelling of the implanted component itself have been reported. Similarly, large gaps can not be efficiently repaired, partially due to the fact that the implant material will potentially be too heavy. Furthermore, current materials are limited to a tubular (tunnel shaped) design which prevent the surgeon from seeing the nerve segments that are being handled once inserted into the implant. Finally, existing peripheral nerve repair devices require sutures for attaching the nerve stumps to the nerve repair device. Such suturing can lead to damage of the axons and require an intensely careful and well developed technique in order properly handle the nerve bundle.
As such, there is a need to develop novel implant materials and designs that avoid these problems and produce greater ease of use and provide a scaffold for cellular growth over larger distances.